Dynamos, which convert natural energy of fluids, such as tidal currents and river flows, to electric energy, have been known. Such dynamos employ mechanisms to spin a rotor by turning rotating components, such as propeller blades, with, for example, wind or water flow.
Such rotating components, however, have complex structures, which may increase the manufacturing costs of the dynamos. Additionally, the rotating components in use may be damaged by a drifting object, which is present in a flow field and entangled in the rotating components. Creatures present in the flow field, such as fish, may also be entangled in the rotating components to be harmed.
Another type of dynamo, which has been known, uses an oscillator that is located in a flow field of a fluid to oscillate. Specifically, this type of dynamo includes a columnar body placed with its longitudinal direction intersecting with the flow direction of the fluid, and the oscillation of the columnar body causes a permanent magnet to move inside coils, which generates an induced current to the coils thereby generating electricity.
In other words, this type of dynamo described above effectively uses the oscillation energy of fluid-induced oscillations, caused in the flow field, of the oscillator to generate electricity.